| 摘要 |
<p>This invention is a prosthetic spinal disc nucleus (20) for implantation into a nucleus cavity of a spinal disc. The nucleus cavity is defined by an opposing pair of vertebral bodies, and an annulus. The prosthetic spinal disc nucleus has a formed hydrogel core (22) configured to expand from a dehydrated state to a hydrated state. The hydrogel core is wedge shaped in at least the hydrated state. The constraining jacket (24) surrounding the hydrogel core is flexible, but substantially inelastic, and has a generally fixed maximum volume less than a volume of a nucleus cavity such that the constraining jacket is configured to prevent the hydrogel core from conforming to an annulus upon hydration.</p> |
